Resistance-unit terminal



W. C. WHITE.

RESISTANCE UNIT TERMINAL.

APPLICATION FILED MAR. 15, 1920.

1,394,055. I Paitented 0011.18, 1921.

Inventor: William C. White,

b fi fw l His Attorneg.

WILLIAM G. WHITE,

OF SCHENECTA DY, NEW YORK, ASSIGNOR TO GENERAL E LEGTRIC COMPANY,econronazrion or new YORK.

RESISTANCE-UNIT TERMINAL.

To all whom it may concern:

Be it known that I, WILLIAM G. WHITE, a citizen of the United States,residing at Schenectady, in the county of Schenectady, State of NewYork, have invented certaln new and useful Improvementsin Resistance-Unit Terminals, of which the following is a specification.

The present invention relates to conductors of high resistivity andcomprises a novel current conveying terminal whereby conductors of thistype may be conveniently and efficiently connected in circuit.

It has been suggested heretofore to reduce the resistance of theterminals of resistors by dipping the resistors in carbonizable materialand baking it at carbonizing temperature. This method is not alwaysapplicable, especially when the resistors COIlSlSt lar ly ofclose-grained Vitreous matenlal, suc as porcelain.

In accordance with my invention, theresistor is treated with; asuspension of conductive material, so finely divided as to penetrateinto the pores of a surface layer of the resistor as well as tosuperficially coat the same. I preferably provide a terminal thus coatedwith a coating of metal, preferabl by winding the same with wire.

he accompanying'drawing illustrates in perspective one embodiment of myinventlon.

The rod 1 consists of a vitreous material,

such as porcelain containing in solution a cable. This mixture issquirted in stick form, dried and fired in an ordinary porcelain kiln attemperatures'of about 1340 to 1370 degrees C. Resistors of thisparticular type do not constitute a part of m present invention, and aredescribed and c aimed in the copending ap lication, Serial No. 365,738filed by Elmer lfi. F. Creighton.

In order to provide terminals for resistance bodies of the abovedescribed class, the finished resistors are dipped in a suspension offinely divided graphite or equivalent Specification of Lette'rs Patent.Pat t d t, 1 1921. Application filed March 15, 1920. Serial No. 365,830.

this term to designate suspensions ofgraphite of colloidal fineness. inwater. The suspension of graphite penetrates the surface layer only ofthe resistance material. The article thus treated is allowed to dry andthe excess is then wiped off, leaving at the ends .2 and 3 a glossyblack surface Teseii ibling pure graphite. The surface 'film of gra beenreduced to such a fine state of subdi-' -state.- For examplefI may dipthe endso'f v its is of relatively high conductivity. In

order to protect this film from mechanical injury it is covered with alayer .of metal. As shown on the drawing, a convenient way of coveringthe graphite contact surfaces-is to wind them with a layer of closelycoiled wire 4, 5, consisting of brass, copper, nickel,

or the like. The electrical connection to the" metal contacts 4, 5 maybe made by usual base 8. Vhat I claim as new and desire to securetherethrough and containing at the surface portions thereofconductivem'aterial of colloidal fineness of subdivision constitutingcurrent conveying terminals. 2. An electrical conductor comprisingporcelain and .a conductive oxid of a metal and containing at thesurface portions thereof finely divided'graphite and a layer of wirewound on said graphite-filled portions.

3. An electrical conductor comprising a solution of "oxid'of iron inporcelain having the terminal surface layers impregnated.

with graphite of a fineness o'f subdivision equal to that of colloidalgraphite and a layer of metal inclosing said terminal surfaces.

4. A conductor of high resistivity comprising a rod of ceramiccomposition containing a conductive material, a surface layer of aquadagon the terminals of said rod and a layer of wire wound on said terminalsover said surface layer. In witness whereof, I have hereunto set my handthis 28th da of F ebrua 1920. WILJIAM C. W IIITE.

spring clips 6, 7, mounted upon an insulatby Letters Patent of theUnited States is 7 1. An electr cal conductor comprising avitreousmaterial, a conductor distributed

